Yes it is based on the 0.360" 2 1/4" BPE and one should be able to form from it. Buffalo Arms forms the 0.360" 2 1/4" from 30-40 Krag. I'll check but I think Mike Ford who has penned a series in the GGCA publication has formed some. I hope the example doesn't see a reamer.

Kind Regards,

Raimey
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